Synthesis and antiviral bioactivities of novel chiral bis-thiourea-type derivatives containing α-aminophosphonate moiety

Starting from 1-((1R,2R)-2-aminocyclohexyl)-3-substituted thioureas (3a–c) and substituted isothiocyanates (9a–d), chiral bis-thiourea derivatives containing α-aminophosphonate moiety 10a–l were prepared and completely characterized by elemental analysis, physical and spectral (IR, 1H NMR, 13C NMR, 31P NMR) data. The results of bioassay revealed that compounds 10a and 10e possessed appreciable curative bioactivities on cucumber mosaic virus (CMV) at 0.5 mg/mL in vivo (inhibitory rate = 60.3%, 64.8% respectively) and tobacco mosaic virus (TMV) at 0.5 mg/mL in vivo (inhibitory rate = 50.3%, 50.8% respectively), which were comparable to the values shown by standard reference (58.7%) and commercial product Ningnanmycin (56.3%), respectively. Chiral compound 10e displayed more potent antiviral activity (EC50 = 0.149 mg/mL) than Ningnanmycin (EC50 = 0.201mg/mL) against CMV.